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MartinJ

power levers issue

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Hi,

 

I'm using a GoFlight throttle quadrant to control the throttles in X-Plane. I assigned one lever to each throttle so I have separate control over both throttles. When using the Saab I noticed its throttle levers behaving strangely.

 

After starting the engines I set both throttles to ground idle. Now if I gently move the throttles forward by a tiny bit one or both engines go to max reverse. After advancing the throttles a little bit more they start following the actual hardware throttle input again. Same for the other direction. I set the throttle to ground idle and start moving them a little bit in the reverse thrust position. When I do this one or both throttles go to max reverse until I move the throttles a little bit more.

 

I've already checked my GoFlight throttles and there is nothing wrong with them. They are properly calibrated and additionally no other aircraft shows this strange behaviour. Also note that this error only occurs with engines running which suggests some sort of flawed code. 

 

Thank you!

Martin

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After starting the engines I set both throttles to ground idle.
The throttles should be set to "ground idle" during startup, not after.

 


Now if I gently move the throttles forward by a tiny bit one or both engines go to max reverse. After advancing the throttles a little bit more they start following the actual hardware throttle input again. Same for the other direction. I set the throttle to ground idle and start moving them a little bit in the reverse thrust position. When I do this one or both throttles go to max reverse until I move the throttles a little bit more.
Just to be clear.... when you say "one or both", is it different every time you start the Saab?  Is there ever an instance where it does not happen at all?  Also, to be clear... they are always moving to max reverse thrust when this happens, correct?

 


I've already checked my GoFlight throttles and there is nothing wrong with them. They are properly calibrated ...
I assume you mean they are properly calibrated using the "Calibrate joystick Hardware " button in the "Joystick & Equipment" window?

 


Also note that this error only occurs with engines running which suggests some sort of flawed code. 
Again, to be clear, if you move the throttles when the engine are NOT running, they behave as they should, correct?  This is very strange as the code that handles the throttles does not take into account whether the engines are running or not, so it shouldn't matter.

 

As no one else has reported this I'm inclined to believe it is unique to your hardware.  Perhaps there is another Saab user with GoFlight hardware who can help out.

 

If you want to, you can use DataRef Editor to monitor this DataRef... "sim/cockpit2/engine/actuators/throttle_ratio", to see what values are being sent from your hardware to the throttles.  The code simply uses that value, so if it's no good at that point you have a hardware issue.

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First thank you for your quick reply.

 

 

 

when you say "one or both", is it different every time you start the Saab?

 

There's no way of telling which throttle will go to max reverse when leaving the ground idle detent. It differs every time both throttles are being moved out of the ground idle detent. What I've noticed a few minutes ago is that it does not depend on whether the engines are running or not. Instead it depends on the position of the condition levers. As long as they are not at min or forward of it everything works fine. Set the condition levers to min and the problem is there.

 

 

 

they are always moving to max reverse thrust when this happens, correct?

 

Yes.

 

 

 

if you move the throttles when the engine are NOT running, they behave as they should, correct?

 

See my text above.

 

It is definitely not a hardware failure as it also happend with my old joystick before I got my throttle quadrant.

 

Please take a look at the following picture.

saab.jpg?dl=1

 

The picture shows the situation. I moved the right throttle a tiny bit forward and out of the ground idle detent. As you can see the dataref is 0.0 but not because of the throttle input as you can see to the right. X-Plane's joystick menu also shows that the right throttle input is definitely not zero.

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Martin,

 


There's no way of telling which throttle will go to max reverse when leaving the ground idle detent. It differs every time both throttles are being moved out of the ground idle detent.

This pretty much confirms that this is not a code issue, but rather a hardware issue.  The code behaves the same every time, especially as there are no other conditions affecting the operation.  However, it is possible that the hardware could be hypersensitive, or can produce noise and/or cross-talk, which can vary each time it is used.

 

The condition levers have absolutely no interaction with the throttles at all, so they cannot be at all related to the problem as far as the code is concerned.  However, if you have your hardware connected to the condition levers, there may be cross-talk or noise affecting the throttles on the same quadrant.

 

I tested this on a CH Products throttle quadrant and a Saitek X52 and could not reproduce this issue.

 

The DataRef I asked you to monitor is simply an input to the Saab in X-Plane.  This Dataref is used by hardware, manipulators, and keyboard comands, and all the tests I have run with these inputs show them to be working fine.  The DataRef will be set to whatever value your hardware sends to it.  If the hardware sends erratic values, it can do so VERY quickly (much faster than the code could pick it up), thereby causing the throttles to misbehave.  Therefore, you get an out-of-sync condition where you may see the proper values in your calibration screen but, until you move the throttles again, they will not sync.  It may not be noticeable in other aircraft as they may not use the input values the same way we do in the Saab.

 

I am open to any other suggestions, but based on other hardware working (as noted above), the manipulators working, and the keyboard input working, this is most definitely not a code issue. 

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I tested this on a CH Products throttle...

 

Just out of curiosity: have you set the "is a CH Products' throttle" option in X-Plane's joystick menu? 

Edited by MartinJ

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Just out of curiosity: have you set the "is a CH Products' throttle" option in X-Plane's joystick menu? 

 

If you are talking about the "CH Products throttle quadrant" check box in the Equipment Tab, then yes.

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May I ask you to deactivate this option and perform the actions I described in my first posts which are:

 

1) set both throttles to ground idle

2) start both engines

3) set both condition levers to max

4) move the throttles a tiny bit back and forth out of the ground idle detent and check the Saab's throttles

 

Yesterday I set the "CH Products throttle quadrant" option and noticed that the error I described was gone. Instead there was a new one which lead to the throttles jump to max thrust when selecting max reverse.... 

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I experience the same problem with Saitek X-52 Pro. Joystick is very sensitive around ground idle and self set one (ususally right) power lever to full reverse as described by MartinJ.

Edited by Jara4

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Martin,

 

I do not have the time to test various hardware configurations.  Maybe another user can help you with specific hardware questions/issues.  At this point I think it is clear that these problems are not directly related to the Saab.

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Hi Martin

 

I am not quite sure i am understanding your problem. I do have a Goflight GF-TQ6-ADV quadrant, not the same model than yours, but i am not experiencing any problem with the saab.

 

I will share you my experience.

 

When you start xplane and you load the saab340 having your goflight hardware throttle levers fully closed/retarded, the saab 340 doesn't know what your actual hardware levers positions are. The saab340 will configure its throttle levers at ground idle as supposed to be encountered upon entering the cockpit in the real thing.

BUT your hardware levers are fully retarted/closed, which means they are actually physically on the max reverse position, low end of its travel.

 

You already have a SYNC issue which is ok, the saab has its throttle levers set at ground idle, but your hardware levers is fully retarded in the MIN position 0.0 of its travel, but neither the saab or xplane knows about it until you move them physically for the first time which will send a signal to the simulator about its position for the saab/xplane to pickup.

 

I.E. assuming your hardware levers are in fully closed/retarded position (0.0) when loading xplane/saab340:

 

As soon as you move them tiny bit (any or both levers) xplane/saab knows they are at 0.0, which means low end travel MAX REVERSE position and the saab will jump its throttle levers back to sync them with your hardware actual position. Now they are in sync, you have to move your hardware levers forward by 15% aprox until you reach ground idle and you are all set.

 

is that what you are experiencing?

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@JGregory: The Saab is the only aircraft in my virtual hangar with this particular problem and two other users with different hardware reporting it too but of course it's not Saab related....Maybe it's really not your fault and the problem is caused by X-Plane but shouldn't you be interested in finding out what's causing the problem anyway?

 

@mmerelles: Thanks for your reply. What you described is true but it's actually not the problem I'm experiencing. Please see the steps I described in post #9. What's happening here when performing step 4 is that the left or the right throttle jumps to max reverse when the throttles are moved out of the ground idle detent by a tiny bit. As soon as the throttles are moved a little bit more they are in sync with the hardware input again. I should add that I usually need to move the throttles several times out of the ground idle detent before the problem shows up.

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@mmerelles: Thanks for your reply. What you described is true but it's actually not the problem I'm experiencing. Please see the steps I described in post #9. What's happening here when performing step 4 is that the left or the right throttle jumps to max reverse when the throttles are moved out of the ground idle detent by a tiny bit. As soon as the throttles are moved a little bit more they are in sync with the hardware input again. I should add that I usually need to move the throttles several times out of the ground idle detent before the problem shows up.

 

ok i reviewed carefully your steps again and got your point. It is too late now going bed, but i will test it tomorrow morning to see if i can replicate your behavior and report back my findings.

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Hi Martin

I've worked the problem with Jim with my own hardware (X52 Saitek), and I am having no problems whatsoever.

In saying this, could you please do me a favor and do the following...

Let me know what version of X Plane you are running.

Open X Plane and disable all plug ins except Gizmo.

Load up the Saab.

Visually confirm your hardware is calibrated in the hardware tab in the sim.

Do not start the aircraft and do not supply any power.

Try the hardware.

If the problem persists, re-calibrate your hardware, but assign BOTH Power Levers to 1 axis.

Test again and please post back.

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I recently installed X-Plane 10.42 (fresh install, not an update), and I am experiencing a similar problem. In 10.36 everything was fine, but since using 10.42 this is what happens: When the trottle-lever is at idle, the right throttle in the sim sometimes jumps to full reverse. Sometimes it jumps back to idle by itself, sometimes I need to add a little bit of power to "reset" it.

 

I am using a custom throttle quadrant using one of Leo Bodnars USB-Interfaces. I have assigned both throttles to the same lever. Everything is calibrated in X-Plane. As soon as I set some amount of power, the problem is gone.

 

I don't think that it's a hardware problem, because I don't experience this problem with any other plane in X-Plane or FSX/P3D. I also tried to move all custom plugins apart from gizmo out of the plugins-folder, but that didn't fix it, unfortunately.

Of course I was thinking of this at first (e.g. a bad potentiometer), but when I am monitoring the output values for the throttle levers in FSUIPC, I don't see any jumping values which could cause this issue.

Edited by mgeiss

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The Saab is the only aircraft in my virtual hangar with this particular problem ...

My belief is that because of the custom handling of the throttles in the Saab, the problem is "revealed".  It doesn't mean that the issue doesn't exist with other aircraft.  It also doesn't mean that the Saab code is wrong.   ie.  In the 172 there is no reverse and therefore there still may be an issue but it just doesn't have the same effect as in the Saab.

 

Maybe it's really not your fault and the problem is caused by X-Plane but shouldn't you be interested in finding out what's causing the problem anyway?

Interested?... not sure that would be the right description.  Of course we want all our customers to be happy, but an issue being reported by 2 or 3 people out of thousands is not a significant priority.

 

I recently installed X-Plane 10.42 (fresh install, not an update), and I am experiencing a similar problem. In 10.36 everything was fine,

This just further strengthens my statement that the issue is not in the Saab code.  Perhaps something changed in 10.42, but I am not seeing it with the hardware I have.

 

In addition, from what I can tell by your reports this is not something that you can consistently and repeatedly reproduce with the exact same results. And now we have a report of it happening in 10.42 but not 10.36.  It is extremely difficult to diagnose something without a set of a parameters that can reproduce the problem.  

 

I am not abandoning this, I just cannot test hardware when the Saab code is, and has been, functioning as it should. I also do not have every piece of hardware available on the market to try out.

 

I would certainly be interested in hearing from all users who utilize hardware for throttles.  Tell us what version of XP you are using and if you have issues or not.

Edited by JGregory

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I will try to analyze the issue further. E.g., maybe the problem is only there with the engines running or it only begins to show after a certain point through the startup process.
I only made two flights with the Saab since using 10.42, so I didn't have much time for further investigations.

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I would certainly be interested in hearing from all users who utilize hardware for throttles.

 

 

Jim,

 

I have had this problem for as long as i can remember. I did not brought this before as i was expecting this to be contested "hardware problem". But while we're on this topic ...

I'm using Thrustmaster Warthog. I've used a lot of controllers over the last 20 years, there really is no jitter on this piece of hardware. Happens only in X-Plane & only in the Saab.

 

- goes full reverse with PL near GND IDLE (NEVER happened for me with PL >= FLT IDLE - so only on the ground)

- i'm not 100% certain, but i think it's right PL only for me

 

Currently running 10.45b2

As soon as i'll have some time (propably tomorrow) i'll test for this and give you more details.

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Note:  For anyone reporting in this thread about a problem with the Throttles... please post as much info as you can about your system, ie. Windows/Mac, OS version, XP version, etc.

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Here we go:

 

Windows 10

X-Plane 10.45b2

GoFlight TQ6 throttle quadrant, assigned to throttle 1 and 2, other axes are not in use

No other plugins are in use 

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Windows 7 x64

X-Plane 10.42

Custom built trottle control with a USB interface from Leo Bodnar

 

Both power levers are assigned to the same axis, only the right lever shows the problem in the sim.

Edited by mgeiss

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Note:  For anyone reporting in this thread about a problem with the Throttles... please post as much info as you can about your system, ie. Windows/Mac, OS version, XP version, etc.

 

 

Here you go Jim...

 

Windows 8.1 (64-bit)

X-Plane 10.45b2

 

And here are my findings:

- only right PL (i hope others can also confirm this)

- only with CL between MIN and MAX

- jitter happens at the GND IDLE stop and forward of it until about 3/4 way to FLT IDLE, then it's ok

- once you get out of the "jitter zone" (by moving PL to FLT IDLE or further forward) the jitter won't reappear until you move PL back to GND IDLE and wait for the engine to spool down to idle speed (or very close to it)

- 100% not hardware related - confirmed by reassigning my THR1 axis to THR2 and vice versa (it's always right PL in the sim)

Edited by niebieski

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